package cn.itcast.directory;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements View.OnClickListener{
    MyHelper myHelper;
    private EditText mEtName;
    private EditText mEtPhone;
    private TextView mTvShow;
    private Button mBtnAdd;
    private Button mBtnQuery;
    private Button mBtnUpdate;
    private Button mBtnDelete;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        myHelper = new MyHelper(this);
        init();
    }
    private void init(){
        mEtName = (EditText) findViewById(R.id.et_name);
        mEtPhone = (EditText) findViewById(R.id.et_phone);
        mTvShow = (TextView) findViewById(R.id.tv_show);
        mBtnAdd = (Button) findViewById(R.id.btn_add);
        mBtnQuery = (Button) findViewById(R.id.btn_query);
        mBtnUpdate = (Button) findViewById(R.id.btn_update);
        mBtnDelete = (Button) findViewById(R.id.btn_delete);
        mBtnAdd.setOnClickListener(this);
        mBtnQuery.setOnClickListener(this);
        mBtnUpdate.setOnClickListener(this);
        mBtnDelete.setOnClickListener(this);
    }
    @Override
    public void onClick(View v){
        String name;
        String phone;
        SQLiteDatabase db;
        ContentValues values;
        switch (v.getId()){
            case R.id.btn_add:
                name = mEtName.getText().toString();
                phone = mEtPhone.getText().toString();
                db = myHelper.getWritableDatabase();
                values = new ContentValues();
                values.put("name",name);
                values.put("phone",phone);
                db.insert("information", null, values);
                Toast.makeText(this,"信息已添加",Toast.LENGTH_SHORT).show();
                db.close();
                break;
            case R.id.btn_query:
                db = myHelper.getReadableDatabase();
                Cursor cursor = db.query("information",null,null,null,null,null,null);
                if(cursor.getCount() == 0){
                    mTvShow.setText("");
                    Toast.makeText(this,"没有数据",Toast.LENGTH_SHORT).show();
                }else{
                    cursor.moveToFirst();
                    mTvShow.setText("Name : "+cursor.getString(1)+" ; Tel : " + cursor.getString(2));
                }
                while (cursor.moveToNext()){
                    mTvShow.append("\n"+"Name:"+cursor.getString(1)+";Tel:"+cursor.getString(2));
                }
                cursor.close();
                db.close();
                break;
            case R.id.btn_update:
                db = myHelper.getWritableDatabase();
                values = new ContentValues();
                values.put("phone",phone = mEtPhone.getText().toString());
                db.update("information", values,"name=?",new String[]{mEtName.getText().toString()});
                Toast.makeText(this,"信息已修改",Toast.LENGTH_SHORT).show();
                mTvShow.setText("");
                db.close();
                break;
            case R.id.btn_delete:
                db = myHelper.getWritableDatabase();
                db.delete("information",null,null);
                Toast.makeText(this,"信息已删除",Toast.LENGTH_SHORT).show();
                mTvShow.setText("");
                db.close();
                break;
        }
    }
    class MyHelper extends SQLiteOpenHelper{
        public MyHelper(Context context){
            super(context,"itcast.db",null,1);
        }
        @Override
        public void onCreate(SQLiteDatabase db){
            db.execSQL("CREATE TABLE information(_id INTEGER PRIMARY KEY AUTOINCREMENT,name VARCHAR(20),phone VARCHAR(20))");
        }
        @Override
        public void onUpgrade(SQLiteDatabase db,int oldVersion,int newVersion){

        }
    }
}
